Nationwide Address Nationwide House Pipers Way Swindon SN3 1TA 01793 655198 James.Rowlands@nationwide.co.uk Nationwide is the world's largest building society as well as one of the largest savings providers and a top-three provider of mortgages in the UK. More Close Nationwide Nationwide is the world's largest building society as well as one of the largest savings providers and a top-three provider of mortgages in the UK. It is also a major provider of current accounts, credit cards, ISAs and personal loans. Nationwide has around 15 million customers. The Society has around 18,000 employees. Nationwide's head office is in Swindon with administration centres based in Northampton, Bournemouth and Dunfermline. The Society also has a number of contact centres across the UK.